Dehydration process to impart wrinkle resistance to cellulose-containing fibrous materials

ABSTRACT

Crosslinking formulations are applied to cotton and other cellulose-containing textiles and made to react by dehydrating the impregnated textile at ambient temperatures and pressures.

United States Patent 1191 Kullman et a1.

1 1 DEHYDRATION PROCESS TO IMPART WRINKLE RESISTANCE TOCELLULOSE-CONTAINING FIBROUS MATERIALS [75] Inventors: Russel M.Kullman. Metairie;

Robert M. Reinhardt, New Orleans. both of La.

[73] Assignee: The United States of America as represented by theSecretary of Agriculture, Washington, DC.

[22 Filed: July 25. 1972 [211 App1.No.:274,949

[521 US. Cl. 8/186; 8/187; 8/1164 [51] Int. Cl. D06M 13/34 [58] Field ofSearch 8/1164. 189, 181-187.

1 56] References Cited UNITED STATES PATENTS 3.224.926 12/1965 Bernurdin8/1164 X NOV. 11, 1975 3.264.054 8/1966 Reinhardt et 31.... 8/1 16.43.278.470 10/1966 Henshall et a1. 8/1164 X 3.285.690 11/1966 Cooper eta1 8/187 x 3.312.521 4/1967 Stenner 8/1164 3.350.162 111/1967Becltnmn...v 8/1 16.4 X 3.371.983 3/1968 Barber et a1. 8/1 16.43.527.558 9/1970 Tomasino et all 8/189 3.533.728 10/1970 Shippee et a1,8/189 3.653.805 4/1972 Gamnrra et a1, 8/1492 X 3.660.013 5/1972 PLI181118/1492 X 3.706.526 12/1972 Swidler et a1 8/1492 X Primar E.\tU11'lI11'SIp1'1n .1. Lechert. Jr. Attorney. Agent. or Fim1-M. HowardSilverstein. Max D. Hensely [57] ABSTRACT Crosslinking formulations areapplied to cotton and other cellulose containing textiles and made toreact by dehydrating the impregnated textile at ambient temperatures andpressures.

30 Claims. N0 Drawings DEHYDRATION PROCESS T [MPART WRINKLE RESISTANCET0 CELLULOSE-CONTAINING FIBROUS MATERIALS A non-exclusive, irrevocable,royalty-free license in the invention herein described throughout theworld for all purposes of the United States Government, with the powerto grant sublicenses for such purposes, is hereby granted to theGovernment of the United States of America.

This invention relates to the chemical finishing of textiles. Moreparticularly, this invention relates to a process for chemical finishingof cellulose-containing fibrous materials to effect crosslinking andimprovement in wrinkle resistance. Specifically, this invention relatesto a new method of curing a cellulose-containing textile material whichhas been impregnated with certain crosslinking formulations, the noveltycomprising removing moisture upon exposure of the impregnated materialto an unheated, dehydrating atmosphere at ambient temperatures andpressures thereby generating the conditions necessary for reaction of acrosslinking reagent with the cellulose and enhancing wrinkleresistance. Hereinafter this novel method of textile processing isreferred to as dehydration curing.

THE PRIOR ART There are several processes for producing improved wrinkleresistance in cellulosic materials. That most commonly employed is thepad-dry-cure process. Curing is accomplished in this type of process bysubjecting the impregnated material to a strongly heated atmosphere(usually 140" to 180C). Another method of treatment employed is the mildcure finishing process wherein the curing is accomplished with heatingat mild temperatures of 60 to 100C, so that moisture content within thefiber is critically controlled. This method re quires precise adjustmentof the moisture content in the material being treated.

In another process of the prior art for improved wrinkle resistance, thefibrous material is cured by maintaining a moist condition at about 25Cfor from 4 to 30 hours,, then neutralizing, washing, and drying. Wetfinishing treatments also are known wherein the reaction of thecellulosic fiber proceeds while the fiber is maintained at a level ofswelling which is controlled by composition of the treatment bath.

Various modifications have been reported in the literature to achieveimproved wet wrinkle resistance or improved wet and dry wrinkleresistance wherein the fibrous material must be (1) exposed to elevatedtemperatures during curing (considerably higher than ambient roomtemperatures), as in the pad-dry-cure and mild cure processes; or (2)maintained at a predetermined moisture level during curing, as in moistor wet processes.

Among the advantages of the present invention over the prior art are thesavings of heat energy afforded, the greater comfort of workers by theabsence of elevated temperatures usually encountered in finishingplants, and particularly the superior levels of wrinkle resistance andchlorine resistance of fabrics treated by the process. The value ofwrinkle resistance in textile materials is widely recognized by thoseskilled in the art. It has been estimated that current annual productionin the United States alone of fabric for use in durable press andwrinkle reistant products is about three billion yards.

The main object of the present invention is to provide a process forimparting improved wrinkle resistance by the chemical finishing ofcellulose-containing textiles without subjecting the textile to elevatedtemperatures, without the need of maintaining moisture content in thefibers at critical levels, and without the need for controlling swellingof the fibers through adjustment of the composition of the treatmentbath.

We have unexpectedly discovered that reaction between certaincrosslinking formulations and cellulosecontaining textiles can beeffected readily by the process of our invention. Said process requiresno heating during curing and no controlled levels of moisture norswelling of the fiber. By the process of this invention the fibrousmaterial can be dried and cured by treatment with unheated dehydratingair at ambient temperatures and pressures after impregnating thecellulosecontaining textile with the crosslinking formulation andremoving the excess by conventional squezze-roll techniques.

The instant invention can best be described as a process for impartingwrinkle resistance to cellulose-containing fibrous material, the processcomprising:

a. impregnating the cellulose-containing fibrous material with aformulation containing about from 5 to 25 weight percent of acrosslinking agent selected from the group consisting of glyoxal,formaldehyde, dimethylol dihydroxyethyleneurea, and dimethylol methylcarbamate and about from 0.1 to 1.2 weight percent of an inorganic acidcatalyst selected from the group consisting of hydrochloric acid,hydrobromic acid, sulfuric acid, sulfurous acid, phosphoric acid,phosphorous acid, nitric acid, and nitrous acid,

. removing the excess quantity of formulation to obtain a wet pickup ofabout to percent, and exposing the fibrous material of step (b) to adehydrating atmosphere at ambient temperatures and pressures, forperiods of time about from 30 minutes to 24 hours, the longer periods oftime being employed with a static dehydrating atmosphere and the shorterperiods of time being employed with a dynamic dehydrating atmosphere.

An optional step can be inserted between above steps (b) and (c) whereinthe wet fibrous material of step (b) is dried to a moisture contentintermediate between that of the wet fabric and complete dryness bypassing the impregnated material through a conventional drying oven. Thetime of dehydration treatment necessary to produce a given level ofwrinkle resistance in fabric can be markedly decreased by such a partialdrying step.

The productsproduced by the process are part of this invention. Thesehave outstanding qualities both high dry and wet wrinkle resistance andhigh levels of resistance to damage due to retained chlorine.

By the process of the present invention fibrous material to be employedtherein may be in the form of fibers, yarns, and fabrics; either wovenor knitted. The material may be composed entirely of cellulosic fibers,

either natural or regenerated, or may be composed of said cellulosics ascomponents with other non-cellulosic natural and synthetic components.

PREFERRED REAGENTS Preferred reagents for use in the process of thisinvention are difunctional and polyfunctional chemical agents that reactwith the hydroxyl groups of cellulose under acidic conditions. Theseagents include formaldehyde adducts (methylol derivatives) ofnitrogenous compounds, such as dimethylol alkyl carbamates, dimethyloldihydroxyethyleneurea, dimethylol propyleneureas, and the like; modifiedmethylol agents, such as N-methoxymethyl, N-isopropoxymethyl, andN-acetoxymethyl derivatives, and the like; monoaldehydes, such asformaldehyde; and dialdehydes, such as glyoxal. The concentration of thecrosslinking chemical agent employed in the process may be varied in therange of from about 2.5 percent to 35 percent by weight, based on thetotal weight of the finishing solution. The preferred range is fromabout to about percent.

The catalyst employed in the formulation may be an organic acid, astrong Lewis acid, or a mineral acid. The preferred catalyst is aninorganic acid such as hydrochloric, sulfuric, nitric acid and the like.Concentration of the catalyst in the treating solution may be variedfrom about 0.025 to about 2.5 weight percent but we have found that therange of 0.1 to 1.2 weight percent to be preferred in this invention.

Additives known to those skilled in the art may be used in the treatingsolution for supplementary effects such as softness of hand and thelike.

THE DEl-IYDRATION STEP Dehydration curing by the process of thisinvention is carried out after impregnation of the fibrous material witha solution containing the chemical crosslinking agent and catalyst, oralternately, after partially drying the impregnated material.impregnation may be accomplished by any suitable means. For fabrictreatments, impregnation is most commonly accomplished by immersing thefabric in the treatment solution, then squeezing out excess solution bypassing through pad rolls which also facilitates uniform penetration anddistribution of the treatment solution within the fibrous material.Based upon the dry weight of the material, a wet pickup of about 60 to100 percent is preferred.

The fibrous material may then, as shown in the following Examples, bepartially dried before curing under ambient pressures and temperatures.The material is heated for about from 1.5 to 7 minutes at a temperaturesufficient to partial dry the material, e.g., about 60 C.

Curing conditions which may be employed in the process of this inventioninclude exposure of the suitably impregnated fibrous material to astatic or a dynamic (moving) dehydrating atmosphere under ambientpressures and temperatures of about from 20 to 30C, for periods of aboutfrom 30 minutes to 24 hours. Time required can vary depending uponselection of a static or dynamic dehydrating atmosphere. An afterwash ofthe treated fabric by any conventional washing procedure is done aftercuring to remove residual catalyst, unused reactant, and byproducts.After-washing 4 may be omitted with some catalysts as the cured material regains moisture on removal from the dehydrating atmosphere, saidmoisture may be sufficient to dilute and render any remaining catalystor acidic material innocuous.

In summary, this invention provides a process (and products by saidprocess) for finishing fibrous materials containing a cellulosiccomponent to produce a product with improved wrinkle resistance. Wrinkleresistance as a useful fabric property is well known and is a necessityfor durable press garments that are in such demand by American and otherconsumers. The curing treatment of the process is carried out in thepresence of an unheated, dehydrating atmosphere. The process may besummarized as:

a. impregnating the fibrous material containing a cellulosic componentto about -100 percent wet pickup of of a solution containing 5-25percent of a chemical agent capable of crosslinking the cellulosiccomponent, and an inorganic acid catalyst; and

b. exposing the impregnated material to a static or a dynamic unheateddehydrating atmosphere at ambient temperatures and pressures, forperiods of time sufficient to effect the crosslinking reaction toproduce a fibrous material having improved wrinkle resistance.

The following examples are set forth to illustrate certain significantaspects of the invention, and should not be construed as limiting theinvention in any manner whatever.

EXAMPLE I Swatches of cotton printcloth were padded to about percent wetpickup with an aqueous solution containing 15 percent (wt./wt.) ofdimethylol methyl car- -bamate and 0.4 percent (wt./wt.) of hydrogenchloride (from hydrochloric acid). These swatches were divided intoGroups A, B, and C. Samples from each group were partially dried in a60C atmosphere for 1.5, 3, 5, and 7 minutes which reduced the moisturecontents to about 40, 18, 4, and 3 percent, respectively. Group Asamples, A-l.5, A-3, A-5, and A-7, immediately after partial drying wereneutralized in a dilute solution (approximately 1 percent, wt/wt) ofsodium carbonate, then washed and dried. Group B samples, B-l,5, 8-3,3-5, and 13-7, after partial drying were placed in a reaction chamber incontact with a dehydrating atmosphere (static conditions, normalpressures) over 150, desiccant at 25C for 22 hours, removed, neutralizedin the sodium carbonate solution, then washed and dried. Group Csamples, C-1.5, C-3, G5, and C-7, after partial drying were immediatelysealed in plastic bags and maintained at constant moisture levels for 22hours at 25C, removed, neutralized in the sodium carbonate solution,then washed and dried. Results are shown in Table 1.

TABLE l-continued Partial Moisture I: Strength drying content WRA,W+Fretention in Sample (min. at after HCHO N deg Cl-scorch 60C) partial DryWet test drying B-5 5 4 4.42 1.27 272 290 95 8-7 7 3 4.32 1.40 261 28896 01.5 1.5 40 0.73 0.31 189 180 2 C-3 3 18 1.56 0.44 I92 254 7 C-5 5 43.30 L03 269 282 36 C-7 7 3 3.87 1.10 270 27S 65 These data show thatsamples of Group B, the pro- EXAMPLE 4 cess Of the present invention,are SUPCI'IOT I11 reaction 5 Swatches of cotton printcloth were paddedto about efficiency as seen by high nitrogen and formaldehyde contents,high wet and dry wrinkle recovery angles, and high levels of strenthretention in the chlorinationscorch test (AATCC Test Method 92-1967,American Association of Textile Chemists and Colorists). The

' data also reveal that partial drying to too low a level of moisturecontent prior to exposure to an uneated dehydrating atmosphere gives alower wrinkle recovery than do treatments in which samples with highermoisture levels are exposed to the unheated dehydrating atmosphere.Furthermore, prevention of moisture loss during the curing reaction asin the treatments of Group C does not produce comparably high levels ofwet wrinkle recovery nor of strength retention in thechlorination-scorch test.

EXAMPLE 2 Swatches of cotton printcloth were padded to about 90 percentwet pickup with a solution containing percent (wt./wt.) of formaldehydeand 0.4 percent (wt/wt.) of hydrogen chloride. Four samples werepartially dried as in Example 1 for 1.5, 3, 5, and 7 minutes,respectively. These samples were coded D-l.5, D-3, D-5, and D-7. Inaddition, one sample coded D-O, was not partially dried. The sampleswere treated in a dehydration chamber over P 0 desiccant at 25C forhours, removed, washed, and dried. Results are shown in Table ll.

TABLE ll WRA, W+F, deg. Sample HCHO Dry Wet D- 0.82 247 276 D-1.S 1.18287 286 D-3 1.21 284 289 D-5 1.17 283 279 D-7 1.39 288 281 From thesedata it is shown that the new process for producing improved wrinkleresistance is effective with monoaldehyde crosslinking agents.

EXAMPLE 3 percent wet pickup with a solution containing 15 percent(wt./wt.) of dimethylol methyl carbamate and 0.4 percent (wt./wt.) ofhydrogen chloride. These swatches were divided into Groups E and F andpartially dried in a 60C atmosphere for 3 minutes (about 18 percentmoisture content). Group E swatches, 5%, E36, E-l E-2, and 13-3, afterpartial drying were placed in a dehydration chamber over P 0 desiccant.An inlet and outlet connection on the chamber allowed unheated,anhydrous air to be passed into, through, and out of the chamber duringdehydration of the E samples. Ambient air at 25C was made anhydrous bybubbling through concentrated sulfuric acid and used for the treatment.B samples were treated by this procedure for A, 34, l, 2, and 3 hours at25C. They were coded E-r, E-ik, E-l E-2, and E-3, respectively. Afterthe treatment, they were removed, neutralized in sodium carbonatesolution as in Example 1, then washed and dried. Samples F- l F2, andF-3 were placed in the dehydration chamber over P, O, desiccant at 25Cfor l, 2, and 3 hours, respectively as done for B samples in Example 1.They were then removed, neutralized in the sodium carbonate solution asin Example 1, washed and dried. Results are shown in Table III.

From data in this table, it is seen that development of dry wrinklerecovery by the new process may be accelerated greatly by dynamicconditions in which anhy drous air at 25C is passed through the reactionchamber during the dehydration curing treatment.

EXAMPLE 5 A swatch of cotton printcloth was padded to about percent wetpickup with a solution containing 15 percent (wt.lwt.) of dimethylolmethyl carbamate and 0.4 percent (wt/wt.) of hydrogen chloride. Thewetimpregnated fabric was placed in a dehydration chamber as in Example4 but in the absence of P 0 Ambient air at 28C was'made anhydrous bypassing through a heat exchange coil immersed in a dry ice (solid C0,)-acetone bath at 67C such that moisture in the air was condensed, frozen,and thus removed. The anhydrous air was then passed through glass coilsto achieve a TABLE IV Time after sample Chamber insertion Chamberrelative temperature. in chamber humidity C 65 28 minutes 785 28 45minutes 80.5 28 3 hours 52 28 The dry wrinkle resistance of the finishedfabric was 262 and the wet wrinkle resistance was 264.

The initial increase in relative humidity is due to the moistureintroduced by the wet-impregnated fabric. During the course of reactionbetween the finished agent and cellulose more water is produced whichalso contributes to imcreased humidity. This is seen in the followingequation which represent the crosslinking reaction that produces wrinkleresistance.

Cellulose-OH HOCH, CH,OH HO-Cellulose N l c OCH,

H catalyst Cellulose-OCH,NCH,O-Cellulose 2H,0

OCH,

Dehydration of the fabric and the reaction has occurred to a sufficientextent after three hours at a constant temperature to produce a wrinkleresistant fabric. The relative humidity after three hours reflects thatthe dehydration of the fabric and the reaction have approachedcompletion.

EXAMPLE 6 A swatch ofa fabric comprised of an equiweight mixture ofpolyester and cotton was padded to about 80 percent wet pickup with asolution containing 25 percent (wt/wt) of dimethylol methyl carbamateand 0.6 percent (wt/wt) of hydrogen chloride. The swatch labelled G, waspartially dried for 3 minutes in a 60C atmosphere, placed in thedehydration chamber over P 0 desiccant at 25C for H6 hours as Sample Ein Example 4 with anhydrous air flowing into, through, and out of thechamber. After removal and washing the sample was tumble dried in anautomatic home dryer, then evaluated for durable press appearance usingthe AATCC 3-dimensional standards.

An untreated swatch, labelled H, of the same fabric containingequiweight mixtures of polyester and cotton after being washed andtumble dried in the same manner as Sample G was also evaluated with theAATCC 3-dimensional standards.

8 Sample G and H were also tested for wrinkle recovery and results areshown in Table V.

TABLE V Sample WRA, W-t-F,deg. Durable Press Rating Dry Wet after tumbledrying This shows that the new process is effective in improving durablepress performance, as measured by improvement in dry and wet wrinklerecovery and smoothness appearance as measured by the durable pressrating of fabrics containing up to 50 percent by weight of a cellulosiccomponent.

EXAMPLE 7 Four swatches of cotton printcloth were labelled l, J, K, andL respectively. Swatches were padded to about percent wet pickup withsolutions as identified in the following data:

HCl in Dimethylol methyl treatment carbamate in treatment Swatchsolution solution I 0. l4 5 I 0.28 10 K 0.59 25 TABLE VI WRA. dryDurable Press Rating after Sample Tumble Drying I 225 2.7 J 259 3.7 K270 4.5 L 206 L0 Improvement in wrinkle recovery and smoothnessappearance was achieved in each instance over a wide range ofconcentration of catalyst and crosslinking agent by use of this newprocess over the untreated sample (Sample L).

EXAMPLE 8 Swatches of cotton printcloth, labelled M and N were padded toabout 90 percent wet pickup and aqueous solutions identified below:

Swatch %H,SO. DMDHEU M 0.6 Is N 1.2 [5

"DMDHEU is dat m, a .cn-n crosslinking agent.

The swatches were partially dried for 3 minutes in a 60C atmosphere,placed in the dehydration chamber over P 0, desiccant at 25C for 1%hours as Sample E in Example 4 with anhydrous air flowing into, throughTABLE. VI]

Sample WRA. dry Durable Press Rating after Tumble drying L (untreated)206 L This demonstrates that the process is useful with other mineralcatalysts and tetrafunctional crosslinking agents.

We claim:

1. A process for imparting wrinkle resistance to cellulose-containingfibrous material comprising:

a. impregnating the cellulose-containing fibrous material with aformulation containing about from 2.5 to 35 weight percent of acrosslinking agent and about from 0.025 to 25 weight percent of aninorganic acid catalyst,

b. removing the excess quantity of formulation to obtain a wet pickup ofabout 60 to 100 weight percent, and

c. exposing the fibrous material of step (b) to a dehydrating atmosphereat ambient temperatures and pressures, for periods of time about from 30minutes to 24 hours.

2. A process for imparting wrinkle resistance to cellulose-containingfibrous material comprising:

a. impregnating the cellulose-containing fibrous material with aformulation containing about from 2.5 to 35 weight percent of acrosslinking agent selected from the group consisting of: glyoxalformaldehyde dimethylol dihydroxyethyleneurea, and dimethylol methylcarbamate and about from 0.025 to 2.5 weight percent of an inorganicacid catalyst selected from the group consisting of: hydrochloric acidhydrobromic acid sulfuric acid sulfurous acid phosphoric acidphosphorous acid nitric acid, and nitrous acid,

. removing the excess quantity of formulation to obtain a wet pickup ofabout 60 to 100 weight percent, and

. exposing the fibrous material of step (b) to a dehydrating atmosphereat ambient temperatures and pressures, for periods of time about from 30minutes to 24 hours, the longer periods of time being employed with astatic dehydrating atmosphere and the shorter periods of time beingemployed with a dynamic dehydrating atmosphere.

3. The process of claim 2 wherein the crosslinking agent is glyoxal.

4. The process of claim 2 wherein the crosslinking agent isformaldehyde.

5. The process of claim 2 wherein the crosslinking agent is dimethyloldihydroxyethyleneurea.

6. The process of claim 2 wherein the crosslinking agent is dimethylolmethyl carbamate.

7. The process of claim 2 wherein the inorganic acid catalyst ishydrochloric acid.

8. The process of claim 2 wherein the inorganic acid catalyst ishydrobromic acid.

9. The process of claim 2 wherein the inorganic acid catalyst issulfuric acid.

10. The process of claim 2 wherein the inorganic acid catalyst issulfurous acid.

1 l. The process of claim 2 wherein the inorganic acid catalyst isphosphoric acid.

12. The process of claim 2 wherein the inorganic acid catalyst isphosphorous acid.

13. The process of claim 2 wherein the inorganic acid catalyst is nitricacid.

14. The process of claim 2 wherein the inorganic acid catalyst isnitrous acid.

15. A process for imparting wrinkle resistance to cellulose-containingfibrous material comprising:

a. impregnating the cellulose-containing fibrous material with aformulation containing about from 2.5 to 35 weight percent of acrosslinking agent and about from 0.025 to 2.5 weight percent of aninorganic acid catalyst,

b. removing the excess quantity of formulation to obtain a wet pickup ofabout 60 to weight percent,

c. heating the fibrous material for about from 1.5 to 7 minutes at atemperature sufficient to partially dry said material, and

d. exposing the fibrous material of step (c) to a dehydrating atmosphereat ambient temperatures and pressures.

16. A process for imparting wrinkle resistance to cellulose-containingfibrous material, comprising:

a. impregnating the cellulose-containing fibrous material with aformulation containing about from 2.5 to 35 weight percent of acrosslinking agent selected from the group consisting of: glyoxalformaldehyde dimethylol dihydroxyethyleneurea, and dimethylol methylcarbamate and about from 0.025 to 2.5 weight percent of an inorganicacid catalyst selected from the group consisting of:

' hydrochloric acid hydrobromic acid sulfuric acid sulfurous acidphosphoric acic phosphorous acid nitric acid, and

nitrous acid removing the excess quantity of formulation to obtain a wetpickup of about 60 to 100 weight percent, and

c. heating the fibrous material for about from 1.5 to 7 minutes at atemperature of about 60 C. and

d. exposing the fibrous material of step (c) to a dehydrating atmosphereat ambient temperatures and presures for periods of time about from 30minutes to 24 hours.

17. The process of claim 16 wherein the crosslinking agent is glyoxal.

18. The process of claim 16 wherein the crosslinking agent isformaldehyde.

1 1 l2 19. The process of claim 16 wherein the crosslinking 25, Theprocess of claim 16 wherein the inorganic agent is dimethyloldihydroxyethyleneurea. id catalyst i h h i acid,

20. The process of claim 16 wherein the crosslinking The process ofclaim 16 wherein the inorganic agent is dimethylol methyl carbamate.

21. The process of claim 16 wherein the inorganic 5 acid catalyst ishydrochloric acid.

22. The process of claim 16 wherein the inorganic acid catalyst ishydmbmmic acid 28. The process of claim 16 wherein the inorganic 23. Theprocess of claim 16 wherein the inorganic acid catalyst is nitrous acidaid at l t i lf i id 29. The product produced by the process of claim 2.24. The process of claim 16 wherein the inorganic 0- Th Pr duct producedby the process of claim 16. acid catalyst is sulfurous acid.

acid catalyst is phosphorous acid.

27. The process of claim 16 wherein the inorganic acid catalyst isnitric acid.

1. A PROCESS FOR IMPARTING WRINKLE RESISTANCE TO CELLULOSE CONTAININGFIBROUS MATERIAL COMPRISING: A. IMPREGNATING THE CELLULOSE-CONTANINGFIBROUS MATERIAL WITH A FORMULATION CONTAINING ABOUT FROM 2.5 TO 35WEIGHT PERCENT OF A CROSSLINKING AGENT AND ABOUT FROM 0.025 TO 25 WEIGHTPERCENT OF AN INORGANIC ACID CATALYST, B. REMOVING THE EXCESS QUANTITYOF FORMULATION TO BOTAIN A WET PICKUP OF ABOUT 60 TO 100 WEIGHT PERCENT,AND C. EXPOSING THE FIBROUS MATERIAL OF STEP (B) TO A DEHYDRATINGATMOSPHERE AT AMBIENT TEMPERATURES AND PRESSURES, FOR PERIODS OF TIMEABOUT FROM 30 MINUTES TO 24 HOURS.
 2. A process for imparting wrinkleresistance to cellulose-containing fibrous material comprising: a.impregnating the cellulose-containing fibrous material with aformulation containing about from 2.5 to 35 weight percent of acrosslinking agent selected from the group consisting of: glyoxalformaldehyde dimethylol dihydroxyethyleneurea, and dimethylol methylcarbamate and about from 0.025 to 2.5 weight percent of an inorganicacid catalyst selected from the group consisting of: hydrochloric acidhydrobromic acid sulfuric acid sulfurous acid phosphoric acidphosphorous acid nitric acid, and nitrous acid, b. removing the excessquantity of formulation to obtain a wet pickup of about 60 to 100 weightpercent, and c. exposing the fibrous material of step (b) to adehydrating atmosphere at ambient temperatures and pressures, forperiods of time about from 30 minUtes to 24 hours, the longer periods oftime being employed with a static dehydrating atmosphere and the shorterperiods of time being employed with a dynamic dehydrating atmosphere. 3.The process of claim 2 wherein the crosslinking agent is glyoxal.
 4. Theprocess of claim 2 wherein the crosslinking agent is formaldehyde. 5.The process of claim 2 wherein the crosslinking agent is dimethyloldihydroxyethyleneurea.
 6. The process of claim 2 wherein thecrosslinking agent is dimethylol methyl carbamate.
 7. The process ofclaim 2 wherein the inorganic acid catalyst is hydrochloric acid.
 8. Theprocess of claim 2 wherein the inorganic acid catalyst is hydrobromicacid.
 9. The process of claim 2 wherein the inorganic acid catalyst issulfuric acid.
 10. The process of claim 2 wherein the inorganic acidcatalyst is sulfurous acid.
 11. The process of claim 2 wherein theinorganic acid catalyst is phosphoric acid.
 12. The process of claim 2wherein the inorganic acid catalyst is phosphorous acid.
 13. The processof claim 2 wherein the inorganic acid catalyst is nitric acid.
 14. Theprocess of claim 2 wherein the inorganic acid catalyst is nitrous acid.15. A process for imparting wrinkle resistance to cellulose-containingfibrous material comprising: a. impregnating the cellulose-containingfibrous material with a formulation containing about from 2.5 to 35weight percent of a crosslinking agent and about from 0.025 to 2.5weight percent of an inorganic acid catalyst, b. removing the excessquantity of formulation to obtain a wet pickup of about 60 to 100 weightpercent, c. heating the fibrous material for about from 1.5 to 7 minutesat a temperature sufficient to partially dry said material, and d.exposing the fibrous material of step (c) to a dehydrating atmosphere atambient temperatures and pressures.
 16. A process for imparting wrinkleresistance to cellulose-containing fibrous material, comprising: a.impregnating the cellulose-containing fibrous material with aformulation containing about from 2.5 to 35 weight percent of acrosslinking agent selected from the group consisting of: glyoxalformaldehyde dimethylol dihydroxyethyleneurea, and dimethylol methylcarbamate and about from 0.025 to 2.5 weight percent of an inorganicacid catalyst selected from the group consisting of: hydrochloric acidhydrobromic acid sulfuric acid sulfurous acid phosphoric acicphosphorous acid nitric acid, and nitrous acid b. removing the excessquantity of formulation to obtain a wet pickup of about 60 to 100 weightpercent, and c. heating the fibrous material for about from 1.5 to 7minutes at a temperature of about 60* C. and d. exposing the fibrousmaterial of step (c) to a dehydrating atmosphere at ambient temperaturesand presures for periods of time about from 30 minutes to 24 hours. 17.The process of claim 16 wherein the crosslinking agent is glyoxal. 18.The process of claim 16 wherein the crosslinking agent is formaldehyde.19. The process of claim 16 wherein the crosslinking agent is dimethyloldihydroxyethyleneurea.
 20. The process of claim 16 wherein thecrosslinking agent is dimethylol methyl carbamate.
 21. The process ofclaim 16 wherein the inorganic acid catalyst is hydrochloric acid. 22.The process of claim 16 wherein the inorganic acid catalyst ishydrobromic acid.
 23. The process of claim 16 wherein the inorganic acidcatalyst is sulfuric acid.
 24. The process of claim 16 wherein theinorganic acid catalyst is sulfurous acid.
 25. The process of claim 16wherein the inorganic acid catalyst is phosphoric acid.
 26. The processof claim 16 wherein the inorganic acid catalyst is phosphorous acid. 27.The process of claim 16 wherein the inorganic acid catalyst is nitriCacid.
 28. The process of claim 16 wherein the inorganic acid catalyst isnitrous acid.
 29. The product produced by the process of claim
 2. 30.The product produced by the process of claim 16.